Effects of Inoculated Starter of Lactic Acid Bacteria on Quality and Microbial Diversity of Pickled Wax Gourd in Eastern Zhejiang

Lactic acid bacteria (L34) with antibacterial activity obtained from traditional pickled vegetables was used as a fermented starter in the present study. The changes of product quality and microbial diversity were investigated under spontaneous and inoculated fermentations for cooked pickled wax gourd, and analysis of community were conducted by Illumina Miseq sequencing. The results showed that pH in each sample decreased gradually in the first 13 days, then increased slightly and remained stable. About 6 types of organic acids and 17 amino acids were detected, while higher content of lactic acid was found with starter fermentation by L34. The predominant species were Enterobacteriaceae sp. and Bacillus subtilis in the early stage, and transferred to Lactobacillus and Enterobacteriaceae sp. later. In general, microbial diversity of the microflora increased firstly, and then decreased. The composition of microflora varied in different fermentation periods and systems, and the diversity changed rapidly under spontaneous fermentation. Practical Applications Lactic acid bacteria play an important role in the processing and preservation of pickled wax gourd. The changes of microbial diversity as well as the predominant species were investigated under spontaneous and inoculated fermentation for cooked pickled wax gourd, and diversity analysis of community was conducted by Illumina Miseq sequencing. This method could provide information about the variation of microflora compositions in different fermentation systems and fermentation periods, and it can also provide guidance for quality control of pickled wax gourd processing.